(1)  In this regulation –

principal grooves , in relation to a tyre, means wide grooves, other than secondary grooves –

(a) usually positioned in the central zone of the tyre tread but that may run across the tyre tread; and

(b) in which tread wear indicators are usually located;

secondary grooves in relation to a tyre, means shallow grooves in the tyre tread that may disappear during the life of the tyre through wear;

tread wear indicators in relation to a tyre, means projections within a groove of the tyre that indicate the degree of wear on the tyre’s tread.

(2)  A tyre on a light vehicle must not have cleats or other gripping devices that could damage road surfaces.

(3)  Except at tread wear indicators, a tyre fitted to a light vehicle must have a tread pattern at least 1.5 millimetres deep, in all principal grooves on the tyre, in a band that runs continuously –

(a) across the tyre width that normally comes into contact with the road; and

(b) around the whole circumference of the tyre.

(4)  A light vehicle must not be fitted with a tyre that has been treated by recutting or regrooving the tread rubber, unless the tyre was –

(a) constructed with an extra thickness of rubber designed for recutting or regrooving; and

(b) labelled to indicate the construction.

(5)  Subregulations (3) and (4) do not apply to a vehicle designed mainly for use in a specialised activity such as agriculture or road construction.

Examples for subregulation (5) :

Multi-tyred rollers (self-propelled or towed), bitumen-laying machines, mowing equipment (self-propelled or towed)